INTRAVESICAL CAPSAICIN FOR TREATMENT OF DETRUSOR HYPERREFLEXIA

An intravesical instillation of 100 ml 1 or 2 mmol/1 capsaicin has bee n used to treat detrusor hyperreflexia giving rise to intractable urin ary incontinence in 12 patients with spinal cord disease and two other patients with detrusor overactivity of non-spinal origin. Nine patien ts, all of whom had spinal cord disease, showed some improvement in bl adder function. The benefit was only shortlived and partial in four, b ut the remaining five achieved complete continence while performing in termittent self catheterisation. Urodynamic studies in these nine pati ents showed an increase in mean (SD) bladder capacity from 106 (57) to 302 (212) ml and a fall in the maximum detrusor pressure from 54 (20) to 36 (10) cm of water. There were no short term ill effects from the instillation and the improvement in bladder function lasted for betwe en three weeks to six months, when in some patients it was repeated. T he improvement in bladder behaviour shown in this study can be interpr eted as showing that capsaicin sensitive afferents play an important p art in the pathogenesis of detrusor hyperreflexia in spinal humans. In travesical capsaicin seems a promising means of treating intractable d etrusor hyperreflexia and studies with this substance may shed new lig ht on other disorders of detrusor activity that cause incontinence.